DMPesso

Hello everyone, I have a 99 GS300 with 140k and the check engine light has been randomly going on then after turning the car on and off a few times it goes off. This has happened about 4 times so far ever since I was spinning my tires in the snow trying to get out of the pile of snow I was stuck in. I just got it read at auto zone and its code P0763 which seems to be solenoid #3 I believe. It has been somewhat hard shifting when its cold from 1st to second if the RPMS are really low and if im in traffic come to a stop and then press the gas quickly it jerks and lurches forward slightly and has lag in acceleration. Does anyone know if I need to remove the tranny to change the solenoid, one mechanic told me yes then I looked online and someone did it just by dropping the tranny pan. Any thoughts or suggestions are appreciated, thanks everyone.